Guide
Allergens in mayonnaise
Mayonnaise is an egg ingredient. Most UK brands also contain mustard. Both must be emphasised in the ingredients list of any PPDS food that uses the mayonnaise, including a thin spread in a sandwich.
Reviewed against official guidance.SourcesNot legal advice.
The usual pattern
Standard mayonnaise is oil, egg yolk, vinegar and mustard. Reduced-fat versions often add milk or modified starch. Vegan mayonnaise is not egg — and is a different product.
What to check in mayonnaise
| What you see | What it means on a PPDS label |
|---|---|
| Egg yolk | Eggs |
| Mustard flour or mustard | Mustard |
| Some light mayonnaises | Milk |
| Vegan mayo | Often soya — never assume it is allergen-free |
How to write it on the label
PPDS food needs the name of the food and a full ingredients list, with the 14 allergens emphasised every time they appear. The Food Standards Agency’s PPDS guidance is the practical reference. A typical ingredients fragment looks like this — yours must follow the specification of the product you actually use.
Example fragment
Rapeseed oil, water, pasteurised egg yolk, spirit vinegar, sugar, salt, mustard.
Where it shows up
Sandwiches, coleslaw, potato salad, burger sauces and prawn cocktail.
A different tub on the weekend
Switching from egg mayonnaise to a vegan or light version changes the allergens. Update the sandwich label the same day the tub changes.
Mustard is easy to miss because it is a small percentage. It is still an intentional ingredient and must be emphasised.
Specification first
Brands differ. Treat this page as the usual pattern, then match the label to the tub, bag or recipe in front of you.
Questions
Does a scrape of mayo still count?
Is salad cream the same?
Official sources
Everything on this page traces back to these. Where they and we disagree, they are right — tell us and we'll fix it.
- Introduction to allergen labelling for PPDS foodFood Standards Agency / GOV.UK
- Labelling guidance for prepacked for direct sale (PPDS) food productsFood Standards Agency / GOV.UK
- Food allergen labelling and information requirements technical guidanceFood Standards Agency / GOV.UK